// 导出页面为PDF格式
import html2Canvas from 'html2canvas'
import JsPDF from 'jspdf'

export default function (dom, title) {
    //将弹窗body滚动到顶部，不然会截图不全
    return new Promise((resolve, reject) => {
        dom.scrollTop = 0
        html2Canvas(dom, {
            allowTaint: true,
            useCORS:true,
            height: dom.scrollHeight + dom.offsetHeight,
            windowHeight: dom.scrollHeight + dom.offsetHeight,
            onclone:function (html){
                //将明细表展开
                let detailTableList =  html.querySelectorAll(".fks-table");
                if(detailTableList && detailTableList.length){
                    detailTableList.forEach((item)=>{
                        item.style.maxHeight  = '10000px'
                        let tableBody = item.querySelector(".fks-table__body-wrapper")
                        tableBody.style.maxHeight = '10000px'
                    })
                }
            }
        }).then(function (canvas) {
                let contentWidth = canvas.width
                let contentHeight = canvas.height
                //A4纸宽度为592.28，高度为841.89
                let pageHeight = contentWidth / 592.28 * 841.89
                let leftHeight = contentHeight
                let position = 0
                let imgWidth = 595.28
                let imgHeight = 592.28 / contentWidth * contentHeight
                let pageData = canvas.toDataURL('image/jpeg', 1.0)
                let PDF = new JsPDF('', 'pt', 'a4')
                if (leftHeight < pageHeight) {
                    PDF.addImage(pageData, 'JPEG', 0, 0, imgWidth, imgHeight)
                } else {
                    while (leftHeight > 0) {
                        PDF.addImage(pageData, 'JPEG', 0, position, imgWidth, imgHeight)
                        leftHeight -= pageHeight
                        position -= 841.89
                        if (leftHeight > 0) {
                            PDF.addPage()
                        }
                    }
                }
                PDF.save(title + '.pdf')
                resolve()
            }
        )
    })

}